Method for fabricating a barrier layer

1. A method of fabricating a barrier layer, the method comprising: oxidizing a silicon-containing substrate to form a substrate oxide layer on the surface of the substrate; producing an oxygen-impervious layer at an interface between the substrate oxide layer and the substrate; etching the substrate oxide layer until the underlying oxygen-impervious layer is uncovered; depositing a metal layer on a surface of the oxygen-impervious layer; and thermally oxidizing the metal layer; wherein the oxygen-impervious layer forms a barrier to the formation of metal silicide compounds between the deposited metal layer and the substrate.

2. The method of claim 1 , further comprising: providing the oxygen-impervious layer by exposing the substrate oxide layer to a nitrogen-based gas, the oxygen impervious layer comprising a substrate-nitrogen compound.

3. The method of claim 2 , further comprising: selecting the nitrogen-based gas from the group consisting of a N 2 gas, an N 2 O gas, an NO gas and an NH 3 gas.

4. The method of claim 2 , further comprising: selecting the substrate-nitrogen compound to include a silicon nitride.

5. The method of claim 2 , further comprising: selecting the substrate-nitrogen compound to include silicon oxynitride.

6. The method of claim 2 , further comprising: etching the substrate oxide layer in a wet-chemical etching process.

7. The method of claim 2 , further comprising: etching the substrate oxide layer in a dry etching process.